This invention relates generally to stringed musical instruments and more specifically to such instruments having fingerboards, normally on necks thereof.
Stringed musical instruments, such as four-string bass guitars or conventional six-string guitars, are often specialized, most being fretted but some being fretless. Each type instrument has unique identifiable sounds which makes it preferable for use in certain music styles. For examples, a fretless electric bass guitar is very popular for use with jazz music because of its sound, which is similar to that of an upright acoustic bass fiddle, whereas fretted bass guitars are more popular in funk rock and country music.
However, due to changes in musical trends and the merging of various musical styles, new music has been created which combines different aspects of different types of music. Thus, it is no longer uncommon to hear instruments which were previously restricted to certain types of music played together in the same songs with instruments which were restricted to other types of music. Further, many musicians simply enjoy playing in different musical styles. For this reason, many players purchase both fretted and fretless instruments so that they can create the various different types of sounds. Although this allows musicians to play both fretted and non-fretted types of music, it is relatively expensive. Further, it is inconvenient for musicians to have to transport and maintain two different instruments rather than only one. For this reason, it is an object of this invention to provide a stringed musical instrument that can be played either as a fretted instrument or as a fretless instrument.
A related problem is that some music demands that the different sounds of fretted and fretless instruments be played in quick consecutive order, alternating from one type to the other within a song. Even when a musician has two different guitars, for example, it is difficult and extremely inconvenient to continually change instruments, and in some songs it is virtually impossible. For this reason, it is often necessary to have two musicians each playing a different instrument in order to achieve desired different sounds in sequence. Again, it is expensive to provide two musicians for performing music which otherwise could be performed by one performer and also it is difficult for a single performer to provide an adequate performance when he must continually switch instruments. Thus, it is an object of this invention to provide a single stringed musical instrument that can be easily and quickly switched between fretted and unfretted modes of operation.
Several stringed instruments have been suggested which allow transformation between fretted and unfretted operation. For example, U.S. Pat. No. 4,297,936 to Mouton describes an electric bass guitar having laterally retractable frets. In this case, the frets are commonly attached at lateral ends thereof to a flexible thumb bar which runs parallel to a guitar neck. The thumb bar is so flexible that when a player applies lateral pressure, only adjacent frets are activated, with others remaining unperturbed. One difficulty with the guitar of Mouton is that the laterally extending frets get in the way and the guitar does not look or feel like a conventional instrument. Further, there is a fret hold-down tension wire therein which extends the length of the guitar neck and which allows simultaneous movement of all the frets. This wire could create an extraneous vibration, which is undesirable. Further, the frets of this instrument are somewhat cumbersome not being positively secured in their positions nor including a simultaneous positive adjustment of all frets since a wire could tend to bow if a fret meets movement resistance.
Thus, it is an object of this invention to provide a stringed musical instrument that can be played either as a fretted or a fretless instrument, which has an appearance quite similar to that of conventional stringed instruments, which has a positive, accurate and sturdy simultaneous adjustment of all frets, and which does not include an unduly flexible structure which could cause undesirable vibrations.
U.S. Pat. No. 4,722,260 to Pigozzi describes a stringed musical instrument having retracting frets with each fret being driven by two rotating cams, one located on each side of center of the fret. Each fret is separately biased downwardly by a coiled spring acting on a lateral shaft extending into a neck of the stringed instrument. The cams are simultaneously rotated by two longitudinal shafts which are driven by a central pinion attached to a knob. A major problem with the musical instrument of this patent is that the neck thereof is unduly weakened by the structures of the fret actuating mechanisms. Further, because of the positions of these mechanisms, it is not possible to have a normal truss rod running along the neck on a side thereof opposite to the strings to counteract tension of the strings. Yet another difficulty with the stringed musical instrument of Pigozzi is that it appears to be somewhat complicated in structure having many different pieces which require an undue amount of time and undue expenditure of labor to manufacture. Also, the appearance of the guitar itself is not conventional. For this reason, it is an object of this invention to provide a stringed musical instrument whose neck is quite similar in structure and shape to a neck of a normal stringed instrument but yet is quite strong, allowing the use of a normal truss rod to counteract string tension. It is a further object of this invention to provide a stringed musical instrument which has relatively few parts and is therefore relatively easy, and not time-intensive, to construct.
Yet another object of this invention is to provide a stringed musical instrument which can be played both as a fretted and as a fretless instrument, operating effectively in both modes in substantially the same manner as respective conventional fretted and fretless instruments.